Wireless devices exist in everyday life, transmitting position, measuring temperature, determining moisture content or chemical content of soil, determining whether a light is turned on or off, whether it is night or day, etc. Those devices range in size and can often be quite small. Wireless devices may be used to provide sensory data or other information, control actions, or provide computing services, through wireless means to a controller which operates on that data or information in some manner.
On occasion, a wireless device may be in a stationary position for a period of time and be relocated. Or, a wireless device may move regularly, such as between rooms of a house, or between different fields on a farm. When a wireless device moves from one location to another, the wireless device may move out of range of one controller, and into range of a different controller within the same wireless system. At some points, a wireless device may be at a location which is within wireless range of more than one controller.